Sierra Impeller Kit 223-3307, Replaces Westerbeke 34440, for Westerbeke Generators

The Sierra 223-3307 Impeller Kit is a replacement impeller kit built for the raw water pump on select Westerbeke marine generators. The impeller is the wear component inside the generator's raw water circulation pump that draws in cooling water and keeps engine temperatures in check; over time the rubber vanes harden, crack, or shed material, which can restrict cooling flow and lead to overheating if not replaced. This kit is a direct replacement for Westerbeke part number 34440 and is built to Sierra's standard of matching or exceeding the original equipment part it replaces.

The kit is made of metal and rubber construction consistent with OEM-style impeller assemblies, ships as a complete one-count kit, and is sized for a compact raw water pump housing. It is designed to fit a wide range of Westerbeke BCD, BTD, BTDA, BTDB, BTDC, and WMD generator models across both 60Hz and 50Hz configurations, as detailed in the fitment section below. Boat owners performing routine cooling system maintenance or troubleshooting an overheating generator can use this kit as a like-for-like swap for the original impeller.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 223-3307
• Material: Metal
• Item Weight: 0.05 pounds
• Item Dimensions: 6 x 2.5 x 6 inches
• Unit Count: 1
• Product Type: Generator Impeller Kit

Fitment

• Westerbeke generator models: 10.0 BTD (60Hz) / 7.5 BTD (50Hz)
• 10.0 BTDA (60Hz) / 7.5 BTDA (50Hz)
• 11.0 BTD (60Hz) / 8.3 BTD (50Hz)
• 11.0 WMD (60Hz) / 8.3 WMD (50Hz)
• 12.5 BTD (60Hz) / 9.4 BTD (50Hz)
• 12.5 BTDA (60Hz) / 9.4 BTDA (50Hz)
• 12.5 BTDB (60Hz) / 9.4 BTDB (50Hz)
• 12.5 WMD (60Hz) / 9.4 WMD (50Hz)
• 15.0 BTDC (60Hz) / 12.0 BTDC (50Hz)
• 4.0 BCD (60Hz)
• 4.4 BCD (60Hz)
• 4.4 WMD (60Hz) / 3.3 WMD (50Hz)
• 5.0 BCD/BCDA/BCDB (60Hz) / 4.0 BCD/BCDA/BCDB (50Hz)
• 6.0 BCD (60Hz) / 4.5 BCD (50Hz)
• 7.6 BTD (60Hz) / 5.7 BTD (50Hz)
• 7.7 WMD (60Hz) / 5.8 WMD (50Hz)
• 8.0 BTD (60Hz) / 6.0 BTD (50Hz)
• 8.0 BTDA (60Hz) / 6.0 BTDA (50Hz) - only for engines older than March 2004
• 8.0 WMD (60Hz) / 6.0 WMD (50Hz)

Replaces (OEM)

• Westerbeke 34440

Frequently Asked Questions

What does the Sierra 223-3307 impeller kit fit? The Sierra 223-3307 is built for the raw water pumps on Westerbeke generator models including the BCD, BTD, BTDA, BTDB, BTDC, and WMD series in both 60Hz and 50Hz configurations, such as the 10.0 BTD, 11.0 WMD, 12.5 BTDA, and 8.0 BTD lines.

Does this kit replace Westerbeke part 34440? Yes, the 223-3307 impeller kit is a direct replacement for Westerbeke 34440.

Is the 8.0 BTDA generator fitment limited to certain build dates? For the 8.0 BTDA (60Hz) / 6.0 BTDA (50Hz) model, the 223-3307 impeller kit only fits engines built older than March 2004.

What is the impeller kit made of? The Sierra 223-3307 is made of metal and rubber construction, matching the material used in the original Westerbeke impeller assembly.

How much does the 223-3307 impeller kit weigh? The Sierra 223-3307 impeller kit weighs 0.05 pounds.

What are the dimensions of this impeller kit? The Sierra 223-3307 measures 6 x 2.5 x 6 inches as packaged.

How many impellers come in the kit? The 223-3307 kit ships as a single count unit, containing one complete impeller kit.

Is Sierra an OEM or aftermarket brand for Westerbeke parts? Sierra is an aftermarket manufacturer that produces the 223-3307 impeller kit to match or exceed the specifications of the original Westerbeke 34440 part it replaces.

When should I replace the impeller in my Westerbeke generator? Replace the impeller in your Westerbeke generator's raw water pump when the vanes show cracking, hardening, or missing material, or as part of routine cooling system maintenance; the 223-3307 kit is sized to swap in for the original Westerbeke 34440 impeller.

Will the 223-3307 fit both 50Hz and 60Hz Westerbeke generators? Yes, the fitment for the Sierra 223-3307 spans both 50Hz and 60Hz versions of the listed Westerbeke BCD, BTD, BTDA, BTDB, BTDC, and WMD models.

Does the 223-3307 come with a warranty? The Sierra 223-3307 impeller kit is covered under Sierra's customer satisfaction warranty against defects in workmanship.